Playback device and method for providing functionality based on event information retrieved from a playlist

ABSTRACT

Instead of using events stored in the datastream itself, applications can retrieve event information from the playlist on a record carrier such as DVD and blu-disc. By retrieving the event information from the playlist changes in the event information do not require reprocessing of the data stream. In addition the application knows before the start of the playback of the data stream where the events are located and what functionality in terms of resources is required. A better scheduling of resources is thus possible.

The invention relates to a playback device for retrieving a data streamcomprising video data comprising a java processor for processing anapplication, the java processor comprising an input for receiving anevent information, to a Java processor for processing an application,the java processor comprising an input for receiving an eventinformation and to a method for processing an java application.

Such a playback device is known from set top boxes complying with theMHP standard.

Such set topbox comprises a processor for processing an application, forinstance a Java application.

The Java application provides a functionality to the set top box that isrelated to the data stream being played back by the set top box. Forthis the java application receives an event from the MHP video streamthat indicates to the Java application that a certain position in thestream of video information is reached and that the associatedfunctionality is to be provided by the Java application.

The event is stored in the video stream as a DSM-CC stream event.

Storing the event in the stream has the disadvantage that the streammust be reprocessed if an event is to be changed.

It is an object of the invention to provide a method that allows changesto the events without extensive processing of the data stream and whilestill being able to provide event information at the appropriateposition during playback of the video or audio data.

To achieve this objective the method is characterized in that the eventinformation is retrieved from a playlist of the data stream.

By retrieving the event information from the play list that isassociated with the data stream comprising video or audio data the eventinformation is no longer retrieved from the data stream comprising thevideo or audio data. Since the event information is not comprised in thedata stream, reprocessing of the data stream is not required and thedata stream can remain unchanged when the event information is changed.In addition, by retrieving the event information from the play list atiming correlation between the playback of the video or audioinformation in the data stream and the event information can beestablished. The playlist provides the playback device with informationabout when sections of the video or audio stream are to be played back.For instance a chapter mark indicating the start of a chapter can beused to activate functionality provided by a Java application that isrelated to this chapter. In this way the functionality associated to achapter can be provided at the right moment, i.e. coordinated with thestart of the playback of that chapter.

Changing event information requires the reprocessing of the playlist,which results in substantially less processing compared to the situationwhere the data stream must be reprocessed to change event information.In addition the playback device benefits from having the eventinformation in the playlist because it no longer needs to demultiplexthe event information from the data stream, reducing the requiredprocessing resources. An additional advantage is that the playbackdevice is aware of the event information before the event arrives,because the playlist is retrieved before the events happen, and can thusschedule the launch of applications much better by anticipating the needto start the application and the anticipated processor work load at themoment of the start of the application and at the moment the event isreached during playback.

Hence the event information retrieved from the playlist allows the samefunctionality to be implemented as event information stored in the datastream itself, while avoiding the reprocessing of the data stream inorder to change the event information. The object of the invention isconsequently achieved.

An embodiment of the method is characterized in that the playlistcomprises a mark with a presentation time and that the event informationis information that the playback device reached the mark presentationtime during playback.

The application needs to know when the functionality is to be provided.

The event information is retrieved from the playlist before the event isreached.

The application, now in the possesion of the event informationsubsequently monitors the progress of the playback and provide thefunctionality when the playback has progressed to the point indicated inthe playlist. The application then provides the functionality associatedwith the event.

Alternatively the event information can be provided to the applicationonly at the moment the application must provide the functionality. Theprocessor in the playback device retrieves event information from theplaylist and only provides the event information to the application whenthe processor determines that the playback reached that point in thedata stream corresponding to the event information in the playlist. Thusa regular application can be used. The application does not need tomonitor the progress of the playback of the data stream but relies onother processes running on the processor to monitor the play back of thedata stream. Especially in the case of Java applications this is anadvantage because the Java application does not need to be aware oflower level processes in the playback device and can be kept independentof the underlying hardware.

A playback device according to the invention is characterized in thatthe event information is received from a playlist of the data stream.

By retrieving the event information from the play list that isassociated with the data stream comprising video or audio data theplayback no longer retrieves the event information from the data streamcomprising the video or audio data. Since the event information is nolonger comprised in the data stream, reprocessing of the data stream isnot required and the data stream can remain unchanged when the eventinformation is changed. In addition, by retrieving the event informationfrom the play list a timing correlation between the playback of thevideo or audio information in the data stream and the event informationcan still be established. The playlist provides the playback device withinformation about when sections of the video or audio stream are to beplayed back. For instance a chapter mark indicating the start of achapter can be used to activate functionality provided by a Javaapplication that is related to this chapter.

In this way the functionality associated to a chapter can be provided atthe right moment, i.e. coordinated with the start of the playback ofthat chapter.

Changing event information requires the reprocessing of the playlistonly, which results in substantially less processing compared to thesituation where the data stream must be reprocessed to change eventinformation. In addition the playback device benefits from having theevent information in the playlist because it no longer needs todemultiplex the event information from the data stream, reducing therequired processing resources. An additional advantage is that theplayback device is aware of the event information before the eventarrives, because the playlist is retrieved before the events happen, andcan thus schedule the launch of applications much better by anticipatingthe need to start the application and the anticipated processor workload at the moment of the start of the application and at the moment theevent is reached during playback.

Hence by retrieving the event information from the playlist the playbackdevice is able to provide the same functionality as when the eventinformation is stored in the data stream itself, while avoiding thereprocessing of the data stream in order to change the eventinformation.

The object of the invention is consequently achieved.

An embodiment of the playback device is characterized in that the javaprocessor comprises means for providing the event information to theapplication.

The application needs to know when the functionality is to be provided.

The event information is retrieved from the playlist before the event isreached.

The application, now in the possesion of the event informationsubsequently monitors the progress of the playback and provide thefunctionality when the playback has progressed to the point indicated inthe playlist. The application then provides the functionality associatedwith the event.

Alternatively the event information can be provided to the applicationonly at the moment the application must provide the functionality. Theprocessor in the playback device retrieves event information from theplaylist and only provides the event information to the application whenthe processor determines that the playback reached that point in thedata stream corresponding to the event information in the playlist. Thusa regular application can be used. The application does not need tomonitor the progress of the playback of the data stream but relies onother processes running on the processor to monitor the play back of thedata stream. Especially in the case of Java applications this is anadvantage because the Java application does not need to be aware oflower level processes in the playback device and can be kept independentof the underlying hardware.

A further embodiment of the playback device is characterized in that theplaylist comprises a mark with a presentation time and that the eventinformation is information that the playback device reached the markpresentation time during playback. A mark can have a presentation timewhich is the time in the playback of the data stream when thepresentation of a section of the data stream commences or stops.

This an event. A functionality can be associated with this event. Anapplication is used to provide this functionality.

A further embodiment of the playback device is characterized in that themark is a chapter mark or a skip mark or a link mark.

Chapter marks, skip marks and link marks are already defined in theplaylist.

It can be beneficial to provide functionality through a Java applicationto the user when a new chapter on the record carrier starts, or ends.For instance when an interactive record carrier complying with the DVDor blu-disk standard reaches a new chapter, the functionality mayinclude displaying an interactive menu specially tailored to the videocontent of the chapter reached. Similar functionality may be provided inassociation to the skip mark or the link mark.

A further embodiment of the playback device is characterized in that themark is reserved for use by the application

Special marks may be inserted in the playlist The special marks are notrecognized by the playback device as regular playlist entries and thuscurrent playback devices that do not comprise this invention can stillcorrectly playback the information on the record carrier. Playbckdevices comprising the present invention recognize the special marks andprovide the special marks to the Java application. All advantages ofstoring the event information in marks in the playlist as discussedabove are maintained when special marks are placed in and retrieved fromthe playlist while compatibility with the existing playback devices ismaintained as well.

A further embodiment of the playback device is characterized in that themark comprises further information for the application.

Application information may be appended to the mark. In that case theevent information is derived from the mark itself while in addition theapplication information is provided to the application started by theevent information.

This allows more flexibility and more customization of the functionalityprovided by the application. Because current playback devices do notrecognize the additional information the additional information isignore during playback and compatibility of a record carrier comprisingadditional information in the playlist for existing marks is achieved.

A Java processor according to the invention is characterized in that theevent information is received from a playlist of a video stream.

By retrieving the event information from the play list that isassociated with the data stream comprising video or audio data theplayback no longer retrieves the event information from the data streamcomprising the video or audio data. Since the event information is nolonger comprised in the data stream, reprocessing of the data stream isnot required and the data stream can remain unchanged when the eventinformation is changed. In addition, by retrieving the event informationfrom the play list a timing correlation between the playback of thevideo or audio information in the data stream and the event informationcan still be established. The playlist provides the playback device withinformation about when sections of the video or audio stream are to beplayed back. For instance a chapter mark indicating the start of achapter can be used to activate functionality provided by a Javaapplication that is related to this chapter.

In this way the functionality associated to a chapter can be provided atthe right moment, i.e. coordinated with the start of the playback ofthat chapter.

Changing event information requires the reprocessing of the playlistonly, which results in substantially less processing compared to thesituation where the data stream must be reprocessed to change eventinformation. In addition the playback device benefits from having theevent information in the playlist because it no longer needs todemultiplex the event information from the data stream, reducing therequired processing resources. An additional advantage is that theplayback device is aware of the event information before the eventarrives, because the playlist is retrieved before the events happen, andcan thus schedule the launch of applications much better by anticipatingthe need to start the application and the anticipated processor workload at the moment of the start of the application and at the moment theevent is reached during playback.

Hence by retrieving the event information from the playlist the playbackdevice is able to provide the same functionality as when the eventinformation is stored in the data stream itself, while avoiding thereprocessing of the data stream in order to change the eventinformation. The object of the invention is consequently achieved.

The invention will now be described based on figures.

FIG. 1 shows a playback device comprising a java processor.

FIG. 2 shows the application layers.

FIG. 3 shows a flow chart of the method where the top level applicationlayer monitors the progress of the playback of the data stream.

FIG. 4 shows a flow chart of another embodiment of the method where theintermediate layer monitors the progress of the playback of the datastream.

FIG. 1 shows a playback device comprising a java processor.

The playback device 2 is arranged for retrieving data, comprising a datastream, from the record carrier 1. The record carrier can be a DVD or aBlu-disk or any other record carrier comprising a data stream comprisingvideo information and a playlist. The playback device comprises a basicengine 3 for retrieving the data form the record carrier 1. The basicengine 3 is connected to a processor 4 via a bidirectional interface.The processor can, via the bidirectional interface, instruct the basicengine to retrieve data from locations on the record carrier 1 indicatedby the processor 4. The processor 4 can thus instruct the basic engine 3to retrieve a playlist from the record carrier 1 and to retrieve datacomprising a data stream, or sections there of, from the record carrier1. After the processor 4 received the playlist from the basic engine 3,the processor 4 retrieves event information form the playlist in a firstsection 7 of the processor 4 and monitors whether the playback of therecord carrier reached the location of one of the events retrieved fromthe playlist. When the playback reaches the location of an event thefirst section of the processor provides the event information to asecond section 6 of the processor that is used to run an application forproviding a certain functionality when the location of a certain eventis reached during playback. The application run by the second section 6of the processor receives the event information and provides afunctionality for instance in the form of video information to bedisplayed on a television set or monitor coupled to the playback device2. In order to provide the functionality the second section 6 provides,in the example of video information, the video information to an outputmeans 8 in the processor. The output means 8 provides the received videoinformation obtained from the second section 6 to an output 9 of theplayback device 2. The output 9 is connected to a television set or amonitor for viewing the video information.

The first section 7 comprises monitoring means to monitor the progressof the playback of the video information but can also comprise thedecoding of the video information. The first section is in that casealso coupled to the output means 8 in order to provide the videoinformation to the output 9 of the playback device 2.

The output device can consequently, if provided with the videoinformation of the functionality provided by the application and thevideo information obtained from decoding the video information in thedata stream, output both at the same time, for instance by providing thevideo information from the data stream full screen and inserting thevideo information associated to the functionality provided by theapplication that received the event information into video informationfrom the data stream. In case the functionality associated with theevent provided by the application is a menu, the playback of the videoinformation from the data stream can be halted until a choice from themenu is made. The menu can in that case be full screen and the videoinformation from the data stream can be suppressed.

FIG. 2 shows the application layers.

The hardware layer 20 is made independent of the top application layer22 by an intermediate layer 21. Instructions from the top applicationlayer, for instance a Java application are provided to the intermediatelayer 21. The intermediate layer 21 translated the instructions for thehardwrae layer 20, thus allowing the top application layer to becompletely independent of the hardware layer 20.

As explained in FIGS. 3 and 4 there are two alternative solutions forhandling the event information.

-   -   the top application layer 22 monitors the progress of the        playback of the data stream    -   the intermediate layer 21 monitors the progress of the playback        of the data stream.

When the top application layer 22 monitors the progress of the playbackof the data stream the top application layer 22 requests retrieval ofthe playlist from the record carrier. This request, given to theintermediate layer 21 is translated and the intermediate layer 21requests the retrieval of the playlist by the hardware layer 20.

The hardware layer 20 retrieves the playlist from the recording mediumand provides the playlist to the intermediate layer 21. The intermediatelayer 21 than then translates the playlist into the correct format forthe top application layer 22. The top application layer 22 processes theplaylist and retrieves the event information. Based on the eventinformation the top application level 22 starts monitoring the progressof the playback by requesting playback progress status reports from theintermediate layer 21, which in turn request these playback progressstatus reports from the hardware layer 20. Once a playback progressstatus report is received, from the hardware layer 20 through theintermediate layer 21, indicating that the playback has progressed tothe point in the data stream associated with the event derived from theevent information, the top level application starts providing thefunctionality associated with the event.

When the intermediate layer 21 monitors the progress of the playback ofthe data stream the intermediate layer 21 requests retrieval of theplaylist from the record carrier. The intermediate layer 21 requests theretrieval of the playlist by the hardware layer 20. The hardware layer20 retrieves the playlist from the recording medium and provides theplaylist to the intermediate layer 21. The intermediate layer 21 thanextracts the event information from the playlist. Based on the eventinformation the intermediate level 21 starts monitoring the progress ofthe playback by requesting playback progress status reports from thehardware layer 20. Once a playback progress status report is receivedindicating that the playback has progressed to the point in the datastream associated with the event derived from the event information, theintermediate level 21 provides the event information to the top levelapplication 22 which can then in turn start providing the functionalityassociated with the event.

FIG. 3 shows a flow chart of the method where the top level applicationlayer monitors the progress of the playback of the data stream.

In a first step 30, the top level application requests the retrieval ofthe playlist. Once the playlist is retrieved the event information isextracted from the playlist in a second step 31. The event informationis then provided to the top level application in a third step 32.Subsequently the top level application, in a fourth step 33, requeststhe processor, i.e. as explained an intermediate level applicationrunning on the processor, to monitor the progress of the playback of thedata stream. This intermediate level application running on theprocessor monitors, in a fifth step 34, the progress of the playback ofthe data stream in a fifth step comprising a loop. The intermediatelevel application checks whether the playback has progressed to acertain point. If the playback has not reached the event location theintermediate application continues to monitor.

If the playback reached the event location a report is issued in thefifth step 34 to the top level application, the operation of the fourthstep 33 continuing from this point and advancing to the sixth step 35where the application starts providing the functionality associated withthe event. Thus the event information provided in this case is thelocation of the event. The top level application is aware of themonitoring of the playback and is waiting, expecting a trigger in theform of information about the status of the playback from anotherapplication that actually performs the monitoring.

FIG. 4 shows a flow chart of another embodiment of the method where theintermediate layer monitors the progress of the playback of the datastream.

In a first step 40 the top level application requests the retrieval ofthe playlist.

Once the playlist is retrieved the event information is extracted fromthe playlist in a second step 41. The event information is then providedto the an intermediate level application in a third step 42.Subsequently the intermediate level application, running on theprocessor starts monitoring the progress of the playback of the datastream. The monitoring of the progress of the playback of the datastream in the fourth step 44 comprises a loop. The intermediate levelapplication checks whether the playback has progressed to a certainpoint. If the playback has not reached the event location theintermediate application continues to monitor.

If the playback reached the event location a report comprising the eventinformation retrieved from the playlits is issued in the fifth step 43to the top level application. The method then advances to the sixth step45 where the application starts providing the functionality associatedwith the event. Thus the event information provided in this case is theactual reaching of the event by the playback. The top level applicationis not aware of the monitoring of the playback but gets a trigger in theform of the event information from another application that actuallyperforms the monitoring.

A possible syntax for implementing the invention is shown below.

Proposed New Syntax No. of Syntax bits Mnemonic JavaPlayListMark( ) {    Length 32 uimsbf     number_of_PlayList_marks 16 uimsbf     for(i=0;i < number_of_PlayList_marks; i++) {       Reserved 8 bslbf      mark_type 8 uimsbf       ref_to_PlayItem_id 16 uimsbf      mark_time_stamp 32 uimsbf       entry_ES_PID 16 uimsbf      Duration 32 uimsbf Data_Bytes 8*16 Uimsbf     } }In this example the Data_Bytes allows 16 bytes of data, this number isan example, less is sufficient for most cases.

Value Meaning Note 0x00 Reserved for future use 0x01 Chapter- Seesection X.X.X of application images. mark The duration field shall beset to zero. The entry_ES_PID shall be set to 0xFFFF. Data_Bytes are notdefined in this case 0x02 Skip point See section X.X.X of applicationimages. The duration field shall be set to zero. The entry_ES_PID shallbe set to 0xFFFF. Data_Bytes are not defined in this case 0x03 Linkpoint A mark referenced by a navigation command such as Link MK. Whenthe player encounters a Link point in the process of a User Operationsuch as Chapter Skip, the player simply ignores the mark. The durationfield shall be set to zero. The entry_ES_PID shall be set to 0xFFFF.Data_Bytes are not defined in this case 0x04-0x2F Java Marks A mark usedby a Java Application 0x30-0xFF Reserved for future useIn this example, mark values from 0x04 to 0x2F are defined as Javamarks.

The table below show the current definitions of marks that can be usedas event information in the playlist. It also shows the values that arereserved for future use and that consequently can be used for thepresent invention.

Mark Tables from BD-ROM Draft Spec No. of Syntax bits MnemonicPlayListMark( ) {     Length 32 uimsbf     number_of_PlayList_marks 16uimsbf     for(i=0; i < number_of_PlayList_marks; i++) {       Reserved8 bslbf       mark_type 8 uimsbf       ref_to_PlayItem_id 16 uimsbf      mark_time_stamp 32 uimsbf       entry_ES_PID 16 uimsbf      Duration 32 uimsbf     } }

Value Meaning Note 0x00 Reserved for future use 0x01 Chapter-mark Seesection X.X.X of application images. The duration field shall be set tozero. The entry_ES_PID shall be set to 0xFFFF. 0x02 Skip point Seesection X.X.X of application images. The duration field shall be set tozero. The entry_ES_PID shall be set to 0xFFFF. 0x03 Link point A markreferenced by a navigation command such as Link MK. When the playerencounters a Link point in the process of a User Operation such asChapter Skip, the player simply ignores the mark. The duration fieldshall be set to zero. The entry_ES_PID shall be set to 0xFFFF. 0x03-Reserved for 0xFF future use

The invention claimed is:
 1. A playback device for retrieving a datastream comprising video data, the playback device comprising: aprocessor configured to receive event information from a playlist of thedata stream; and an application for providing functionality associatedwith the event information; wherein the playlist is not included in thedata stream, and the event information is changeable without changingthe data stream, wherein the processor of the playback device retrievesthe event information from the playlist and only provides the eventinformation to the application when the processor determines thatplayback of the data stream reached a point in the data streamcorresponding to the event information in the playlist, wherein theplaylist comprises a mark with a presentation time and wherein the eventinformation is information that the playback device reached the markduring playback, wherein the mark is a chapter mark or a skip mark. 2.The playback device as claimed in claim 1, wherein the mark is reservedfor use by the application.
 3. The playback device as claimed in claim2, wherein the mark comprises further information for the application.4. A method for processing a data stream and event informationassociated with the data stream, the method comprising the acts of:starting playback of the data stream comprising video information oraudio information by a playback device; retrieving by a processor of theplayback device the event information from a playlist of the datastream; and providing the event information to an application forproviding functionality associated with the event information; whereinthe playlist is not included in the data stream, and the eventinformation is changeable without changing the data stream, wherein theprocessor of the playback device retrieves the event information fromthe playlist and only provides the event information to the applicationwhen the processor determines that playback of the data stream reached apoint in the data stream corresponding to the event information in theplaylist, wherein the playlist comprises a mark with a presentation timeand that the event information is information that the playback devicereached the mark during playback, wherein the mark is a chapter mark ora skip mark.
 5. A playback device for retrieving a data streamcomprising video data, the playback device comprising: a processorconfigured to receive event information from a playlist of the datastream; and an application for providing functionality associated withthe event information; wherein the playlist is not included in the datastream, and the event information is changeable without changing thedata stream, wherein the processor of the playback device retrieves theevent information from the playlist and only provides the eventinformation to the application when the processor determines thatplayback of the data stream reached a point in the data streamcorresponding to the event information in the playlist, wherein theprocessor is further configured to establish timing correlation betweenplayback of the data stream and the event information retrieved from theplaylist, wherein the mark is a chapter mark or a skip mark.
 6. Aplayback device for retrieving a data stream comprising video data, theplayback device comprising: a processor configured to receive eventinformation from a playlist of the data stream; and an application forproviding functionality associated with the event information; whereinthe playlist is not included in the data stream, and the eventinformation is changeable without changing the data stream, wherein theprocessor of the playback device retrieves the event information fromthe playlist and only provides the event information to the applicationwhen the processor determines that playback of the data stream reached apoint in the data stream corresponding to the event information in theplaylist, wherein the event information provides the playback devicewith timing information about when a section of the data stream is to beplayed back and the processor is further configured to provide the eventinformation to the application in accordance with the timing informationfor providing the functionality associated with the section inaccordance with the timing information, wherein the mark is a chaptermark or a skip mark.
 7. The playback device of claim 6, wherein thetiming information includes a start of playback of the section, and theprocessor is configured to provide the event information to theapplication at the start of the playback of the section so that theapplication provides the functionality at the start of the playback ofthe section.
 8. A playback device for retrieving a data streamcomprising video data, the playback device comprising: a processorconfigured to receive event information from a playlist of the datastream; and an application for providing functionality associated withthe event information; wherein the playlist is not included in the datastream, and the event information is changeable without changing thedata stream, wherein the processor of the playback device retrieves theevent information from the playlist and only provides the eventinformation to the application when the processor determines thatplayback of the data stream reached a point in the data streamcorresponding to the event information in the playlist, wherein theevent information provides the processor with a start time of a sectionof the data stream to be played back and the processor is furtherconfigured to provide the event information to the application at thestart time for providing a functionality associated with the section atthe start time, wherein the mark is a chapter mark or a skip mark.
 9. Aplayback device for retrieving a data stream comprising video data, theplayback device comprising: a processor configured to receive eventinformation from a playlist of the data stream; and an application forproviding functionality associated with the event information; whereinthe playlist is not included in the data stream, and the eventinformation is changeable without changing the data stream, wherein theprocessor of the playback device retrieves the event information fromthe playlist and only provides the event information to the applicationwhen the processor determines that playback of the data stream reached apoint in the data stream corresponding to the event information in theplaylist, wherein the processor is configured to retrieve the eventinformation from the playlist before an event associated with the eventinformation is reached during playback of the data stream by theplayback device, wherein the mark is a chapter mark or a skip mark. 10.The playback device of claim 9, wherein the processor is configured tomonitor a playback of the data stream and provide the event informationto the application when the event is reached during the playback forproviding the functionality associated with the event when the event isreached during the playback.
 11. A playback device for retrieving a datastream comprising video data, the playback device comprising: aprocessor configured to receive event information from a playlist of thedata stream; and an application for providing functionality associatedwith the event information; wherein the playlist is not included in thedata stream, and the event information is changeable without changingthe data stream, wherein the processor of the playback device retrievesthe event information from the playlist and only provides the eventinformation to the application when the processor determines thatplayback of the data stream reached a point in the data streamcorresponding to the event information in the playlist, wherein theapplication is configured to provide the functionality only when aplayback of the data stream reached the point in the data streamcorresponding to the event information, wherein the mark is a chaptermark or a skip mark.
 12. A playback device for retrieving a data streamcomprising video data, the playback device comprising: a processorconfigured to receive event information from a playlist of the datastream; and an application for providing functionality associated withthe event information; wherein the playlist is not included in the datastream, and the event information is changeable without changing thedata stream, wherein the processor of the playback device retrieves theevent information from the playlist and only provides the eventinformation to the application when the processor determines thatplayback of the data stream reached a point in the data streamcorresponding to the event information in the playlist, wherein theprocessor is configured to monitor playback of the data stream forproviding the application with the event information only when theplayback reached the point in the data stream corresponding to the eventinformation so that the functionality is provided by the application atthe point without monitoring the playback by the application, whereinthe mark is a chapter mark or a skip mark.
 13. A method for processing adata stream and event information associated with the data stream, themethod comprising the acts of: starting playback of the data streamcomprising video information or audio information by a playback device;retrieving by a processor of the playback device the event informationfrom a playlist of the data stream; and providing the event informationto an application for providing functionality associated with the eventinformation; wherein the playlist is not included in the data stream,and the event information is changeable without changing the datastream, wherein the processor of the playback device retrieves the eventinformation from the playlist and only provides the event information tothe application when the processor determines that playback of the datastream reached a point in the data stream corresponding to the eventinformation in the playlist, wherein the processor retrieves the eventinformation from the playlist before an event associated with the eventinformation is reached during the playback of the data stream by theplayback device, wherein the mark is a chapter mark or a skip mark. 14.A method for processing a data stream and event information associatedwith the data stream, the method comprising the acts of: startingplayback of the data stream comprising video information or audioinformation by a playback device; retrieving by a processor of theplayback device the event information from a playlist of the datastream; and providing the event information to an application forproviding functionality associated with the event information; whereinthe playlist is not included in the data stream, and the eventinformation is changeable without changing the data stream, wherein theprocessor of the playback device retrieves the event information fromthe playlist and only provides the event information to the applicationwhen the processor determines that playback of the data stream reached apoint in the data stream corresponding to the event information in theplaylist, wherein the processor monitors the playback of the data streamfor providing the application with the event information only when theplayback reached the point in the data stream corresponding to the eventinformation so that the functionality is provided by the application atthe point without monitoring the playback by the application, whereinthe mark is a chapter mark or a skip mark.
 15. A playback device forretrieving a data stream comprising video data, the playback devicecomprising: a processor configured to receive event information from aplaylist of the data stream; and an application for providingfunctionality associated with the event information; wherein theplaylist is not included in the data stream, and the event informationis changeable without changing the data stream, wherein the processor ofthe playback device retrieves the event information from the playlistand only provides the event information to the application when theprocessor determines that playback of the data stream reached a point inthe data stream corresponding to the event information in the playlist,wherein the event information from the playlist provides the playbackdevice with timing information about when sections of the data streamare to be played back, and wherein functionality provided by theapplication and related to the event information is activated at a startof playback of the sections by the playback device, wherein the mark isa chapter mark or a skip mark.
 16. A method for processing a data streamand event information associated with the data stream, the methodcomprising the acts of: starting playback of the data stream comprisingvideo information or audio information by a playback device; retrievingby a processor of the playback device the event information from aplaylist of the data stream; and providing the event information to anapplication for providing functionality associated with the eventinformation; wherein the playlist is not included in the data stream,and the event information is changeable without changing the datastream, wherein the processor of the playback device retrieves the eventinformation from the playlist and only provides the event information tothe application when the processor determines that playback of the datastream reached a point in the data stream corresponding to the eventinformation in the playlist, wherein the event information from theplaylist provides the playback device with timing information about whensections of the data stream are to be played back, and whereinfunctionality provided by the application and related to the eventinformation is activated at a start of playback of the sections by theplayback device, wherein the mark is a chapter mark or a skip mark.